Despite growing evidence of its effectiveness in protecting against sexually transmitted infection (STI) and certain cancers, vaccination against human papillomavirus (HPV) in the United States has stalled. HPV vaccination completion among females was actually lower in 2012 than in 2011. HPV is the most common STI in the US, causes genital warts, and is associated with cervical, vaginal, vulvar, anal, penile, and throat cancers. HPV vaccine is most effective when given before exposure to the virus, and is recommended for routine administration to 11-12 year old females and males. Health care providers play the primary influential role in parents' decisions to vaccinate, yet too often provie weak recommendations for HPV vaccination. Many parents think their preteens are too young for HPV vaccination and teens are not routinely included in the decision to vaccinate. Missed opportunities to vaccinate against HPV at the same clinical visit with other preteen vaccines are far too frequent. Among unvaccinated girls in 2012, 84% had a health-care encounter where they received another adolescent age vaccine but not HPV vaccine. This research aims to eliminate this gap by transforming clinical care through an improved communication system and ultimately normalizing HPV vaccination at the optimal ages of 11-12. Principles of dissemination (conscious effort to spread an evidence- based innovation, the HPV vaccine) and implementation (adoption of an innovation in specific settings) science are used. The multiple baseline design will include an intervention with communication strategies adapted to rolling groups of practices (n=48) that (1) report to the North Carolina Immunization Registry (NCIR); and (2) agree to use mobile devices and web-based modalities to keep up to date on HPV vaccine and to educate parents and preteens about HPV vaccination. The overall objective is to assess the extent to which providers, parents and preteens respond to these proactive communication strategies by vaccinating preteen girls and boys. The long term goal is to prevent HPV-related disease through early intervention and protection against this STI. The central hypothesis is that providers, parents and preteens are relevant decision makers who can be motivated to complete the HPV vaccination series according to public health recommendations. The aims are to (1) Develop new and adapt existing theory-driven dissemination and implementation strategies to motivate providers, parents and preteens to initiate and complete the HPV vaccine series; (2) Evaluate theory driven dissemination and implementation strategies to stimulate communication among providers, parents and preteens to motivate HPV vaccination and completion of the series; and (3) Determine practice characteristics related to adoption, implementation, and maintenance of these dissemination and implementation strategies to motivate HPV vaccination of preteens. The positive impact is that effective HPV vaccination dissemination and implementation strategies will be available for use in practices to reduce HPV infection and related diseases.